We review the requirements found in the regulations for obtaining the required support for a tax position, concentrating on the methods outlined in Reg. §1.6662-4(d) in the definition of "substantial authority" which are cross referenced multiple times when considering other levels of authority.The materials can be downloaded from http://www.edzollars.com/2008-08-25_Penalty.pdf .The podcast is sponsored by Leimberg Information Services, located on the web at http://www.leimbergservices.com .